Idle Speed: Adjustments

^ Warm engine to operating temperature.

^ Connect tachometer.

^ Turn engine off.

^ Turn all accessories off.

^ Place transmission in park (ATX) or neutral (MTX).

^ Connect a tachometer.

^ Ground the Powertrain Control Module (PCM) Self-Test Input (STI) (ten) pin at the data link connector.

STI And STO Connectors:

^ Start engine

^ Note idle speed.

^ Check the initial ignition timing. Adjust if not 2°±1 BTDC.

^ Start engine check idle speed. Idle speed should be 850±50 rpm . If not within specification, correct with idle speed adjustment screw.

NOTE: This adjustment must be done when the cooling fan motor is not operating.

Idle Air Adjustment Screw:

^ Turn engine "OFF", remove STI ground, and let engine cool.

^ After the engine has cooled start engine, and note idle speed.

^ Does the engine speed up during warm-up when started cold.

YES -- Vehicle Idle speed is fine.


NO -- Go to BPA1. BPA1 - Check IAC Valve Resistance